A private alternative to SpamBayes
Klar filters spam on your Mac, inside Apple Mail. No account, no cloud, nothing to hand over.
If you are weighing up SpamBayes, here is how Klar differs and where each one is the better pick.
| Aspect | Klar | SpamBayes |
|---|---|---|
| Runs on | Your Mac | Your computer or mail server |
| Who can read your mail | No one new during filtering. Classification stays on your device. | No new third party. The classifier and its training data stay on your system. |
| Works with | Apple Mail, with any account: IMAP, Gmail, iCloud, Exchange | Outlook plug-in, POP3 proxy, IMAP filter, command line and server-side workflows |
| Price | Free forever | Free and open source |
Klar fits better when you want a maintained Apple Mail extension with a bundled multilingual model
The honest picks
- SpamBayes
- A flexible open-source statistical classifier that learns from mail you mark as spam or good. Pick it for an older workflow you are comfortable maintaining or for its command-line building blocks. Its official compatibility guidance still centers on Outlook 2010 and Windows 7.
- Klar
- Pick Klar if you read mail in Apple Mail and want a modern multilingual model that runs entirely on your Mac. No account, no cloud, nothing to hand over.
Product and price details from the vendors' public pages, July and August 2026: spambayes.sourceforge.io. Klar is not affiliated with any vendor named here. No vendor endorses Klar. Product names only identify the tools.
Reclaim your inbox
Spam filter for Apple Mail. Free on the App Store.
